【目的】运用Biolog法分析洛克沙胂作用下的土壤微生物群落碳代谢多样性，以揭示洛克沙胂在环境中残留对土壤微生物学性状的影响。【方法】采集新鲜土壤加入不同质量浓度的洛克沙胂溶液混匀，使药物质量分数（以As计）分别为：低质量分数组15 mg· kg-1、中质量分数组75 mg· kg-1、高质量分数组150 mg· kg-1，放置在室温（20～25℃）下培养，于处理后第1、2、3、5、8周分别采取培养土壤，用Biolog法进行分析。【结果和讨论】洛克沙胂对土壤微生物群落碳代谢功能影响显著，且存在一定的剂量依赖效应。经主成分分析，第1周，洛克沙胂低质量分数组（ w＝15 mg· kg -1）土壤微生物群落多样性和对照组差异不明显，第2、3、5、8周，各组土壤微生物群落碳代谢类型差异显著，其中高质量分数组（ w＝150 mg· kg-1）与对照组差异最大。结果表明，洛克沙胂可致土壤微生物群落碳代谢能力与多样性改变，胁迫浓度越高其作用越强。同时，洛克沙胂对土壤微生物群落碳代谢能力与多样性的影响还表现出时间差异，在暴露胁迫的后期（第5、8周），洛克沙胂的影响逐步减弱，可能与洛克沙胂在土壤中发生化学结构改变和降解有关。%Objective To evaluate the effects of roxarsone residues on the microbiological characteristics of soil , the carbon-source metabolic functions of the soil microbial communities exposed to roxarsone and stud -ied by Biolog technology .[Method] Fresh soil with different concentrations of roxarsone solution mix were collected so that drugs were (as As): group 15 mg· kg -1, group 75 mg· kg-1, group 150 mg· kg -1, cultivated at room temperature (20-25 ℃).Soil samples were taken after 1,2,3,5,8 weeks of treat-ment for analysis using Biolog method .[Result and conclusion] The results showed that the carbon-source metabolic functions of the soil microbial communities of groups treated with roxarsone were signifi -cantly distinguished from that of CK , indicating a dose-dependent relationship .The carbon-source meta-bolic functional diversity of soil microbial communities in the lower roxarsone groups ( w=15 mg· kg -1 ) were not significantly different from the control group during the 1 st week .However , the soil microbial community functional diversity in the four groups (control, low, medium and high group) was significant-ly different in the 2nd, 3rd, 5th and 8th week.The difference between control and treatment groups ap-peared to be much more severe with the increase of roxarsone concentration .It is concluded that the car-bon-source metabolic capacity and functional diversity of soil microorganisms in roxarsone treatment groups change with the increase of roxarsone concentration .In the 2nd week and 3rd week, the functional diversity of the soil microbial community of the three roxarsone groups decrease more rapidly compared with that in the 5th week and 8th week, which might be caused by the chemical conversion and degrada-tion of roxarsone in soil .
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